Molecule magic: Electrons line up for magnetic memory

(Image: Journal of the American Chemical Society, DOI: 10.1021/ja200198v)

By Celeste Biever and Melissae Fellet

Moore’s law says that computer power and memory doubles every couple of years. But molecule-sized magnets could make for hard drives that laugh in the face of that law.

To make such tiny magnets, the unpaired electrons in an atom have to be brought in line. When their spins are aligned, the whole atom becomes magnetic.

Researchers at Peking University in Beijing, China, surrounded a single erbium atom with molecules called “ligands” to orient its extra electrons. The ligands are carbon rings, which surround the atom and tug at its unpaired electrons. This helps to prevent the electron spins from flipping their direction and cancelling their neighbour’s magnetic effect.